Surprise, Surprise. Celebrity tattles with The New York Post say the scuffle that broke out during Joaquin Phoenix’s performance at a Belvedere IX party in Miami Wednesday night was “completely staged” for the documentary Casey Affleck is doing on Phoenix’s new career as a rapper.

The retired actor had to be restrained after hopping into the crowd at M.I.A.’s Club L.I.V to confront a heckler.

“But it was a fake fight,” a spywitness told The Post on Friday. “Nobody threw a punch. They were just holding onto each other.”